1. Field of the Invention
The present invention relates to a user's database structure and a method of constructing the same, in particular, to a user's database of tree structure used in Ethernet.
2. Prior Art
In the simple network management protocol (SNMP) and remote monitoring (RMON) system, the user's address data is mapped after Hash Algorithm to the user's database for storage. Thus, for retrieval of the address data from the database, the database must be accessed to locate the user's address data by means of Hash algorithm. As shown in FIG. 1, which depicts the storage status in the conventional user's database. As shown in FIG. 1, the user's database has four layers of storage space. A first user's data is registered in the "O" th layer of storage space 1. After calculation with Hash algorithm, the user's identification (ID) is placed at the user terminal 11. The data of a second user is also first processed at the "O" th layer of storage space 1 with the corresponding Hash algorithm. However, after calculation, the data of the second user will collide with that of the first user. Therefore, calculation with Hash algorithm must be performed for the second time in the first layer of storage space 2. The ID of the second registered user is placed in the user terminal 21 of the first layer of storage space 2. Similarly, whenever a new user is registered, Hash algorithm calculation must begin with the "O" th registered layer of storage space 1. If any collision happens, it is required to move to the next storage space and Hash algorithm calculation is repeatedly performed until available storage space can be located. Hence, the ID of the third registered user is placed in the user terminal 31 in the second layer of storage space. Since a server 41 is the last one to be registered and collision happens among the "O" th through the second layer of storage space, the ID of the server 41 is placed in the third layer of storage space 41. Hence, when collision happens between the calculated addresses, data will be lost and lacks accuracy. Besides, in storage or retrieval of data, due to the random variation in user's address, the required time cannot be efficiently controlled.